Memoria, patrimonio y territorio : 100 sitios de Patrimonio cultural y natural del Departamento Calingasta. Provincia de San Juan, Argentina

Fil: Tabee, Elena. Universidad Nacional de San JuanFil: Orizas, Eduardo. Universidad Nacional de San JuanFil: Henríquez, Griselda. Universidad Nacional de San JuanFil: Nozica, Graciela. Universidad Nacional de San JuanFil: Matar, María Angélica. Universidad Nacional de San JuanFil: Potenzoni, Adriana. Universidad Nacional de San Jua

Lipid and phytosterol oxidation in vegetable oils and fried potato products

This thesis provides new data on the levels of lipid and phytosterol oxidation products (POPs) in French fries and potato crisps consumed in Sweden. The levels of POPs in fried foods have attracted interest in recent years because of their potential harmful health effects. The analytical methods used here for the determination of POPs in commercial prefried French fries, French fries collected from fast food restaurants and commercial potato crisps included transesterification, SPE, GC and GC-MS. Higher amounts of total POPs were generally found in French fries prepared in restaurants (1.5-8.1 µg/g sample) than in prefried French fries (0.1-2.1 µg/g sample). In potato crisps, the total POPs content ranged from 0.5 to 6.8 µg/g sample. In general, no correlation could be established between the POPs content and the fatty acid profile, tocopherol, tocotrienol and sterol content in any of the fried potato products tested. However, these parameters provided information on the type of frying oil used in the preparation of the commercial fried potato products. The possibility of minimising lipid oxidation and POPs formation in some regular and oleic acid-dominated vegetable oils was examined. The oxidative stability was evaluated in these vegetable oils with and without addition of α-tocopherol and the results showed that addition of α-tocopherol (500-20000 µg/g) increased Rancimat stability only in refined olive oil. After heating at 180 ºC for up to 12 h, the levels of POPs generally increased over time in high oleic rapeseed oil, palm olein and refined olive oil. The addition of 0.2% α-tocopherol to refined olive oil decreased POPs formation significantly during heating. Studies on the quality of French fries prepared at 180 ºC in refined olive oil and palm olein in five batches at 1-hour intervals showed a higher content of POPs in French fries prepared in refined olive oil. However, all other frying quality parameters tested, such as total polar compounds, free fatty acids and p-anisidine value, were significantly lower in the French fries prepared in refined olive oil than in those prepared in palm olein

Resource Optimization for the Non-Orthogonal Multiple Access System in Green Mobile Networks

Non-orthogonal multiple access (NOMA) as one of the key techniques is nominated in new generation of mobile networks that can improve spectral efficiency by using the successive interference cancellation (SIC) method. By this method, users can use a shared channel. Optimal use of spectral and power resources as well as efficient users clustering are important aspects of green NOMA communication networks. In this paper, we assume different users based on their channel gains are dispersed in three near, middle, and far areas to the base station in a cell. To avoid interference and imperfect SIC at the use of NOMA benefits simultaneously, we consider a scenario including grouping of three users. Saving spectral and power resources is the feature of the green NOMA scenario. In the following, with the aim of optimal resource allocation in the NOMA cellular network, we propose the optimization problem of power allocation coefficients to users under increasing the overall system throughput. Power consumption can be optimized by properly allocating power to the base station and users, and with a certain power, can provide a desirable efficiency in the cellular network. To find the optimal power allocation coefficients to users, we prove that the optimization problem is concave/convex, then we apply Lagrangian and KKT conditions. According to the achieved results, the proposed scheme provides a 6.97% improvement in low SNRs and a 1% improvement in high SNRs compared to NOMA with constant power coefficients in terms of the sum capacity